Optimum development patterns for northern-adapted barley

Early maturity is an important trait for barley grown in northern latitudes , where crop loss may occur with the onset on inclement autumn weather. Ear ly maturity, however, is associated with reduced grain yield. A better unde rstanding of the relationships between developmental traits and grain yield would enable breeders to select for lines having growth patterns that opti mize the conflicting requirements of high grain yield and early maturity. T hirty-three double-haploid lines and their parents from each of two barley crosses were grown at Palmer, Alaska, USA for four years. Growing degree da ys to maturity, grain fill period, % vegetative period, and grain yield wer e measured. In both crosses, high grain yield was associated with longer ti me to heading and longer % vegetative period. High grain yield was also ass ociated with shorter grain fill period. Selection of lines with relatively long vegetative periods and short grain fill periods is recommended in envi ronments similar to develop plants that will most efficiently use environme ntal resources to optimize higher grain yield and shorter time to maturity.